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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Poluição sonora urbana: principais fontes - aspectos jurídicos e técnicos

Zajarkiewicch, Daniel Fernando Bondarenco 21 May 2010 (has links)
Made available in DSpace on 2016-04-26T20:30:12Z (GMT). No. of bitstreams: 1 Daniel Fernando Bondarenco Zajarkiewicch.pdf: 1457584 bytes, checksum: 9228d57afbee1c29dce9b245b81ca5a2 (MD5) Previous issue date: 2010-05-21 / Sound and noise come along with humanity from the beginning. Yet, was from the Industrial Revolution that noise pollution took unimaginable proportions, becoming a problem of public health. Besides the auditory effects, man suffers from extra-auditory effects produced by noise, which don t lead him do deafness, but cause injuries in health. Noise is not only a nuisance but a kind of pollution, according to the National Environmental Policy Act, because is an acoustic energy. We will examine how national legislation, besides the experience of America and the European Community, deals with noise pollution, in federal, state a local level. Also will examine the competence of each federation member, the National Environmental Policy, regulations of the Nationals Environmental Counsel CONAMA, the urban policy laws and its main instruments, reviewing some state a local laws. Follows a study of the main sources of noise pollution, non-stationary and stationary sources: vehicles, airplanes, bars and restaurants, industries and religious services. Finally, the roll of the Public Power, Public Attorneys and Society in the effectiveness of the Environment protection / Os sons e ruído acompanham a humanidade desde o começo. Todavia, a partir da Revolução Industrial tomou proporções inimagináveis, transformando-se num problema de saúde pública. Além dos efeitos auditivos, o homem sofre os efeitos extra-auditivos produzidos pelo ruído, que não provocam surdez, mas provocam danos à saúde. O ruído não é só um incômodo, mas uma espécie de poluição, de acordo com a Política Nacional do Meio Ambiente, porque é energia acústica. Veremos como a legislação nacional, além da experiência Norte-americana e da Comunidade Européia, lida com a poluição sonora, em âmbito federal, estadual e municipal. Examinaremos a competências dos diferentes entes federativos, a Política Nacional do Meio Ambiente, as Resoluções do Conselho Nacional do Meio Ambiente CONAMA, o Estatuto da Cidade e os seus principais instrumentos, revendo algumas legislações estaduais e municipais. Segue-se um estudo das principais fontes de poluição sonora, fontes móveis e fixas: veículos, aeronaves, lazer, indústrias e cultos religiosos. Finalmente, o papel que o Poder Público, o Ministério Público e a Coletividade têm na efetividade da preservação do meio ambiente
92

The role of expectations and visions of the future in the development of target-based environmental policies : the case of the UK Air Quality Strategy

McKean, Vanessa January 2015 (has links)
Increasingly, policy-makers rely on forecasts to set targets for environmental and health protection. I examine the UK Air Quality Strategies (AQS) for particulate matter (1997-2007). Here policy-makers select and articulate visions for technological and policy developments in order to set targets and policies to achieve them. Despite growing evidence for adverse health effects of particulates, challenging targets in 1997 were followed by two revisions of Objectives without introducing measures for reducing pollution. In 2007 more challenging targets were resumed. This thesis is a study of the formation and evolution of a policy framework: of the interactions and contrasting roles of scientific expertise, wider political discourse, and the ‘futures' presented by actors involved in the policy process. Sociology of Expectations has previously examined the roles of visions in innovation processes. I extended this framework to examine dynamics of visions in the policy-making process. My findings were based on analysis of visions and discourses identified in texts, model data, and interviews. Whilst none of the explanatory factors alone accounted the developments in the AQS, together they provide an explanation of change which highlights the role of learning by policy-makers . Visions for technological development articulated in each version of the AQS were in line with the dominant visions articulated in central government, but over time policy-makers responsible for the Strategy used them to present options for taking action on pollution. Co-construction of the AQS and modelled forecasts enabled policy-makers responsible for the Strategy to articulate visions for technologies and policies to promote taking action to reduce pollutants, and this led to the more action-oriented Strategy in 2007. This thesis proposes that visions can change more quickly than wider political discourses, and as such can provide opportunities for the introduction of new discourses.
93

Investigation Of Emissions And Combustion Kinetics Of Waste Wood Samples With Thermal And Spectral Methods

Yurdakul Yorulmaz, Sema 01 September 2006 (has links) (PDF)
The mechanisms and kinetics of combustion of waste wood as well as the phases during combustion processes are important to eliminate these wastes without any possible damage to environment. In the present study, combustion mechanisms, activation energy and pre-exponential constants, and phases of combustion were investigated for untreated natural pine and treated Medium Density Fiberboard (MDF), plywood and particleboard samples that involve some chemicals and additives. Waste wood samples were heated in air at 10, 20 and 30oC/min heating rates in a Thermo Gravimetric Analyzer (TGA) from room temperature to 900oC. Thermogravimetry (TG) and Derivative Thermogravimetry (DTG) curves for all samples were obtained. The gases formed during combustion reactions were directly fed to a Fourier Transform Infrared Spectroscopy (FTIR) instrument coupled to TGA. Emission characteristics of the samples were determined in-situ by using the FTIR spectrums. As a result of TG analysis, thermal decomposition of treated samples was observed at lower temperatures as compared to the untreated pine sample because of the catalyzing effects of the chemicals in the treated samples. Therefore, there were less flammable products, lower weight losses in the main oxidation region, decrease in the max. weight loss temperatures and formation of more char for treated samples as compared to untreated pine sample. In other words, chemicals used during production of these samples lead to decrease in the combustibility of the treated samples. Thermal kinetic constants for the samples were calculated by using Coats Redfern and Broido Methods. In order to find out the mechanisms responsible for the oxidation of the waste wood samples in different regions, six solid state mechanisms of Coats Redfern Method were tested. As a result of FTIR analysis of the emitted gases from TG analysis, several chemical groups were detected from pine and treated samples. Combustion of all samples revealed some gases containing aromatics, C-H groups, CO2 and CO. However, there were some toxic and carcinogenic gases like formaldehyde, isocyanate group, ammonia, phenyl group and benzoylbromide among the emissions of treated samples which need utmost attention when recovering energy from treated waste woods.
94

Chemical Composition Of Atmospheric Particles In The Aegean Region

Munzur, Basak 01 February 2008 (has links) (PDF)
Daily aerosol samples were collected at the &Ccedil / andarli which is located on Aegean coast of Turkey. A rural site was selected to monitor atmospheric pollution by long range transport. Sampling was performed in both summer and winter seasons, and in total 151 samples were obtained. Concentrations of elements in the samples were measured in order to identify sources and possible source locations of pollutants. Measured concentrations of trace elements at the &Ccedil / andarli station were compared with those measured at various sites around the world and, also in Turkey. As a result of comparison, level of pollution at the Aegean Region was found to be lower than the Mediterranean Region and Black Sea Region. Air flow climatology at &Ccedil / andarli was investigated in order to determine potential source regions for pollutants. Frequency of air flows from Russia and Western Europe are higher suggesting that emissions from these industrial regions affect the chemical composition of particulate matter. Besides these, it was concluded that contributions from Central and Eastern European countries are significantly high because of frequent air mass transport. Concentrations of elements measured at &Ccedil / andarli station were found to show short and seasonal variations. Such variations in concentrations are explained by variations in the source strengths and transport patterns. Positive matrix factorization (PMF) was applied to determine sources of elements and contribution of sources to each element. This analysis revealed 5 sources, two local anthropogenic emissions factor, one soil factor, one sea salt factor and one long range transport factor. Distribution of Potential Source Contribution Function (PSCF) values showed that main sources of SO42- are observed in Bulgaria, Romania, Poland, Ukraine and central part of Aegean region.
95

Development Of Gis Based Trajectory Statistical Analysis Method To Identify Potential Sources Of Regional Air Pollution

Yikmaz, Riza Fikret 01 May 2010 (has links) (PDF)
DEVELOPMENT OF GIS BASED TRAJECTORY STATISTICAL ANALYSIS METHOD TO IDENTIFY POTENTIAL SOURCES OF REGIONAL AIR POLLUTION Yikmaz, Riza Fikret M.Sc., Department of Geodetic and Geographic Information Technologies Supervisor: Prof. Dr. G&uuml / rdal Tuncel Co-supervisor: Assoc. Prof. Dr. Zuhal Aky&uuml / rek May 2010, 186 pages Apportionment of source regions affecting a certain receptor in the regional scale is necessary information for air quality management and development of national policy for exchange of air pollutants with other countries. Source region apportionment can be studied either through numerical modeling or by using trajectory statistics that is a hybrid methodology of modeling and measurements. Each of these approaches has their advantages and disadvantages. In this study treatment of back-trajectory segments in Potential Source Contribution Function (PSCF), which is one of the tools used in trajectory statistics will be investigated, to increase the reliability of the apportionment process. In the current method run in GIS, especially two parameters gains importance. One is that the vertical locations of trajectory segments are not taken into account at present. In this study, how the evaluation of the segments in 3-D instead of 2-D could improve the results will be assessed. The other parameter that is rainfall at each segment will be included in the PSCF calculations and its effects on the spatial distribution of PSCF values will be evaluated. A user interface in Geographical Information System (GIS) will be developed for effective use of improved methodology.
96

Investigation Of Non-methane Volatile Organic Carbon Emissions From Interior Materials Used In The Intercity Buses

Gormez, Baran 01 September 2004 (has links) (PDF)
The objectives of this study are to determine the non-methane volatile organic carbon emissions from the parts used in the interiors of buses at different temperatures and to analyze the components of these emissions. The total non-methane volatile organic carbon (NMVOC) concentrations in various sections of a bus were measured in order to determine the indoor air pollution in the bus. Different samples of the materials used in the interior parts of the buses were provided by the manufacturing company and they were tested in the METU Air Pollution Laboratory in order to see what hydrocarbon components make up this total NMVOC concentration.The results of experiments showed that the leading constituent emitted from the test pieces was toluene. Benzene concentration was very low. This is very important since benzene is a carcinogen and it has very low indoor concentration limits determined by OSHA and NIOSH. When the concentrations of the total NMVOC emitted from various parts are examined, it was seen that the most of the VOC emissions occur from the floor materials and ventilation channel. After measurements were done in two buses the average indoor total NMVOC concentrations were found as 21.15 &plusmn / 5.8 ppmv (as C3H8) and 46.04 &plusmn / 9.2 ppmv (as C3H8) in the first and second bus, respectively. Suggestions were made to the manufacturing company for some replacement of solvents and adhesives, and measurements were repeated with the newly manufactured parts for the bus. The highest concentrations were observed for toluene in these measurements, too. However, the toluene concentration was at least 40% lower than the initial values. Benzene concentrations were again very low. The average indoor total NMVOC concentrations were found as 10.41 &plusmn / 2 ppmv (as C3H8) in the measurements done in the bus decorated with new materials. This concentration was about 50% and 25% of the values measured in the first and the second bus at the beginning of the study, respectively.
97

Investigation Of Emission Factors Of Non-methane Hydrocarbons For Some Widely Used Passenger Cars In Turkey

Onoglu, Irem 01 September 2004 (has links) (PDF)
The objectives of this study are to measure the non-methane volatile organic carbon (NMVOC&#039 / s) emissions from passenger cars in Turkey having gasoline engines, to determine emission factors of these vehicles for BTEX compounds and comparison of emission factors obtained in this study with the emission factors of the other countries. This study was conducted in two parts: The first part was to determine the categories of passenger cars widely used in Turkey, and also to determine the average carbon monoxide (CO) and hydrocarbon (HC) emissions at idle condition for these car types based on the exhaust emission measurements of Ankara &Ccedil / evre Koruma Vakfi (AN&Ccedil / EVA). The second part of the study was to analyze the gas composition of exhaust gasses at different road conditions for BTEX components by using gas chromatography. The results of the study have shown that the cars named under &lsquo / &lsquo / Tofas&rsquo / &rsquo / constitute 31.5% and &lsquo / &lsquo / Fiat&rsquo / &rsquo / 13.1% of the total cars in Turkey and they are manufactured by the same company. Therefore, studies have been performed with &lsquo / &lsquo / Tofas/Fiat&rsquo / &rsquo / cars. The highest emission factors among hydrocarbons investigated in this study were found for toluene and m-xylene. Generally, as driving speed increases the emissions of HC&rsquo / s are found to decrease in concentration. It was interesting to note that the highest emissions occur at 30 km/hr speed which is the mostly used speed in crowded streets and busy intersections. Therefore, it was concluded that it is very important to take measures for emissions in the city traffic. Cold start emissions were also found to be higher than the hot start emissions.
98

Combustion And Co-combustion Of Olive Cake And Coal In A Fluidized Bed

Varol, Murat 01 June 2006 (has links) (PDF)
In this study, combustion performances and emission characteristics of olive cake and olive cake+coal mixture are investigated in a bubbling fluidized bed of 102 mm inside diameter and 900 mm height. The average particle sizes of coal and olive cake used in the experiments were 1.57 mm and 1.52 mm, respectively. Flue gas concentrations of O2, CO, SO2, NOx, and total hydrocarbons (CmHn) were measured during combustion experiments. Operational parameters (excess air ratio, secondary air injection) were changed and variation of pollutant concentrations and combustion efficiency with these operational parameters were studied. The temperature profiles measured along the combustor column was found higher in the freeboard for olive cake than coal due to combustion of hydrocarbons mostly in the freeboard. The location of the maximum temperature in the freeboard shifted to the upper part of the column, as the volatile matter content in the fuel mixture increased. Combustion efficiencies in the range of 83.6-90.1% were obtained for olive cake with the excess air ratio of 1.12-2.30. The corresponding combustion efficiency for coal was 98.4-99.7% under the same conditions. As the CO and hydrocarbon concentration in the flue gas increased, the combustion efficiency decreased. Also co-combustion experiments of olive cake and coal for various mixing ratios were carried out. As the amount of olive cake in the fuel mixture increased, SO2 emissions decreased because of the very low sulfur content of olive cake. In order to increase the combustion efficiency, secondary air was injected into the freeboard which was a good solution to decrease the CO and hydrocarbon emissions, and to increase the combustion efficiency. For the setup used in this study, the optimum operating conditions with respect to NOx and SO2 emissions were found as 1.35 for excess air ratio, and 30 L/min for secondary air flowrate for the combustion of 75 wt% olive cake and 25 wt% coal mixture. Highest combustion efficiency of 99.8% was obtained with an excess air ratio of 1.7, secondary air flow rate of 40 L/min for the combustion of 25 wt% olive cake and 75 wt% coal mixture.
99

Etude de l’impact de la pollution sonore chez un invertébré marin, l’huître Magallana gigas : approches écophysiologique, écotoxicologique et éthologique au laboratoire et sur le terrain / Impact of noise pollution on a marine invertebrate, the pacific oyster Magallana gigas : ecophysiological, ecotoxicological and ethological study in the laboratory and in the field

Charifi, Mohcine 21 September 2018 (has links)
Les activités humaines font peser sur l’écosystème marin de multiples pressions délétères. Pollution chimique, changement climatique, risque d’acidification, débris de plastique et déchets radioactifs ont des impacts sans précèdent. Une pollution de plus en plus reconnu comme majeur est la pollution sonore. La prospection sismique, le battage de pieux et le trafic maritime génèrent des niveaux sonores qui peuvent être extrêmement forts, modifiant fondamentalement le paysage acoustique sous-marin. On sait que de nombreux mammifères marins et poissons entendent le bruit généré par ces activités et que cela altère leur physiologie et leur éthologie. Par contre, chez les invertébrés marins très peu d’études avaient évalué leur capacité à entendre et l’impact de cette pollution sur eux reste à déterminer. Nous avons abordé le problème par une étude de la capacité de perception du son chez l'huître creuse Magallana gigas en utilisant une approche comportementale et physiologique. Nous avons montré que M. gigas entend dans la gamme de fréquences entre 10 et 1000 Hz. Cette analyse nous a permis de caractériser les sources de sons qui contribuent à leur environnement auditif. Au laboratoire, dans un milieu contaminé (i) au cadmium, un métal que nous avons considéré à la fois comme une substance toxique et un marqueur indirect de l'activité ventilatoire, et (ii), par des bruits de cargo, nous montrons un effet répresseur du bruit caractérisé par une diminution de l'activité valvaire, de l'activité ventilatoire et du taux de croissance. Nous rapportons également une diminution de la bioaccumulation du Cd dans les branchies et une modulation de l'expression de certains gènes. Nous avons enfin étudié sur un enregistrement de 2 ans dans le port commercial de Santander, le comportement (incluant les pontes et la croissance) de 3 groupes d’huitres exposés à une forte pollution sonore et à une « qualité de l’eau » considérée dans la littérature comme bonne à très bonne pour une masse d’eau fortement modifiée. Nous avons retrouvé dans notre analyse différents effets que nous avions provoqués ou prédits à partir du travail de laboratoire où nous avions manipulé le bruit seul. Nous concluons que la pollution sonore au sein du port doit diminuer le fitness des huîtres en modifiant leur activité valvaire, la hiérarchie de leurs rythmes biologiques et la croissance. Nos résultats suggèrent que la pollution sonore peut avoir des conséquences importantes sur les invertébrés et présente un risque fort en termes de productivité de l'écosystème. / Human activities introduce multiple harmful pressures on the marine ecosystem. Chemical pollution, climate change, acidification risk, plastic debris and radioactive wastes have significant effects on marine wildlife. Noise pollution is now recognized as a major source of pollution at sea. Seismic exploration, pile driving and marine traffic, among other activities, generate noise at high sound pressure levels altering the underwater acoustic landscape. Many marine mammals and fish hear the noise generated by these activities which have the potential to alter their physiology and ethology. However, very few studies among marine invertebrates had assessed their ability to hear and the impact of noise pollution on them has yet to be determined. We approached the problem by studying sound perception ability in the pacific oyster Magallana gigas using behavioural and physiological techniques. We have shown that M. gigas is sensitive to sound in the frequency range from 10 to 1000 Hz. This characterization allowed us to define sound sources that contribute to their sound landscape. In the laboratory, in an environment contaminated with (i) cadmium, a metal that we considered to be both a toxic agent and an indirect marker of ventilatory activity, and (ii) cargo ship noise, we showed a depressant or repressant effect of noise characterized by a decrease in valve activity, ventilatory activity and growth rate. We also report a decrease in Cd bioaccumulation and some modulation of gene expression. Finally, we studied a 2-year behavioural record performed in the commercial port of Santander (including spawning events and growth) on 3 groups of oysters exposed to high noise pressure levels. In the port of Santander, the "water quality" is otherwise considered by the literature as good to very good for a heavily modified water body. We found in these records different changes that we previously induced and/or produced in the laboratory. We conclude that the noise pollution load occurring within a commercial port must reduce the fitness of oysters by modifying their valve activity, the hierarchy of their biological rhythms and their growth rate. Our results strongly suggest that noise pollution can have significant consequences on invertebrates and presents a high risk in terms of ecosystem productivity.
100

Šíření hluku z objektu pro chov prasat do okolního prostředí. / The spread of noise from building where the breeding pigs are kept into surrounding enviroment.

VÁVRA, Michal January 2012 (has links)
This thesis deals with the evaluation of noise pollution caused by the operation of pig farm in the village Ponedrazka. The aim of this study was to measure noise at predetermined locations, its evaluation and comparison with the current legislative notice. Measurements were carried out during the vegetation growing season as well as during non vegetation season.

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